Shock protection for valve amps onstage?

[basexperience]

Hello lovely BCers. 

My valve head is in for repair at the moment; 3 gigs in 3 days, and the third one saw a poorly secured stage monitor slide off a subwoofer and crash onto the suspended stage. The massive vibration from this busted a valve, and blew a fuse (we think). 

Does anyone know of a shock absorbing system which would fit between a cab and an amp, to try to help mitigate sudden shocks like that?

Ta peeps

Andy W

[Steve Browning]

A towel, folded.